Mechanical calculator.



H. ELLIS.

MECHANICAL CALCULATOR.

APPLICATION FILED OCT. 13. 1914.

l ,203,863. Patented Nov. 7, 1916.

12 SHEETS-SHEET 1.

WITNESSES: INVENTOH 74 43m JUL m i (KM a If? A TTORNEY H. ELLIS.

MECHANICAL CALCULATOR.

APPLICATION FILED OCT. 13. 1914.

Patented Nov. 7, 1916.

12 5HEETSS HEET 2.

Elm

A TTORNEY Patented Nov. 7, 1916.

12 SHEETSSHEET 3- v1 rromvsr H. ELLIS.

MECHANICAL CALCULATOR.

APPLICATION FILED ocr. I3, 1914.

1 ,203,863. Patented Nov. 7, 1916.

12 SHEETSSHEET 4- WITNESSES:

A TTOR/VEY H. ELLIS.

. MECHANICAL CALCULATOR. APPLICATION FILED OCT. 13. I9I4.

1 03,863. Patented Nov. 7, 1916.

I2 SHEETSSHEET 5.

m Hg. 5.

WITNESSES: INVENTOR 0%? 5M l ATTORNEY H. ELLIS. MECHANICAL CALCULATOR. APPLICATION EILED OCT. 13. I9l4..

1,203,863. Patented Nov. 7', 1916.

12 SHEETS-SHEET 6.

INVENTOR WITNESSES. #7 $6M JLJW my @2 A TTORNEY H. ELLIS.

MECHANICAL CALCULATOR.

APPLICATION FILED OCT. 13. 1914.

1 03,863. Patented Nov. 7, 1916.

12 SHEETS-SHEET 7.

WITNESSES:

IN VEN TOR ATTORNEY BY 7 W H. ELLIS. MECHANICAL CALCULATOR. APPLICATION FILED OCT. 13, 1914.

12 SHEETS-SHEET 8.

W/TNESSES: INVENTOI? 5 a 6 m ,4 TTORA/EY Patented Nov. 7, 1916.

H. ELLIS.

MECHANICAL CALCULATOR.

APPLICATION men own. 1914.

1,203,863 Patented Nov. 7,1916.

12 SHEETS-SHEET 9- 5 BY i ATTORNEY H. ELLIS.

MLCHANICAL CALCULATOR.

APPLICATION FILED OCT. 13. 1914.

Patented NOV. 7, 1916.

12 SHEETSSHEET 10.

IN VE N TOR L- L W A TTORN E Y WITNESSES:

H. ELLIS.

MECHANICAL CALCULATOR.

APPLICATION FILED OCT. I3. 1914.

I2 SHEETSSHEET II.

1 ,203,863 Patented Nov. 7, 1916.

WITNESSES:

4 MM m j mvy VENTOR A TTORNE I H ELLIS.

MECHANICAL CALCULATOR.

APPLICATION FILED OCT. 13. 1914.

1 03,863. Patented Nov. 7 1916.

I2 SHEETS-SHEET12- A TTORNEV into a fine description of many elements and tion or .sTAT s HALcoLm ELLIS, or EAST ORANGE, new JnnsnY.

- MECHANICAL cALc nATon.

Specification of Letters Patent.

Patented Nov. 7, 1916.

Application filed-October 13, 1914. Serial No. 866,481.

To all whom it may concern Be it known that I, HALCOLM ELLIS, a citizen of the United States, residing in the city of East Orange, county. of Essex, State of N ew Jersey, have made certain new and useful Improvements in Mechanical Calculators,

of which the following specifications and drawings, hereunto attached, I form a full, clear and exact description.

Class of imientz'on This machine may be classi edas an adding and subtracting machine wherein a plurality of accumulators may be used at one operation of the machine, a common series of actuators used to operate as many accumulators as may be employed and each accumulator being operated for addition or subtraction without regard to which function the other accumulators may be set for, also one'accumulator may be set for totals or sub-totals while the other accumulators are set for either addisubtraction as desired. "7

Object of iacntiom-(l) The object of thisinvention is to provide an accumulator mechanism that may be operated by the rotation of the adding wheels in one direction for the purpose of addition and in the reverse direction'for the purpose of subtraction. (2) ,To provide a tens carrying mechanism that will operate to rotate the adding wheels in one direction when adding, and in the reverse direction when subt acting. (3)To provide a nh accumulatorcagable of either addition or subtraction with a stop mechanism" for limiting the travel of the adding wheels i'na-direction reversefto that employed in addition whenever a total or a sub-total is to, be taken and to provide means for moving this limiting device on the rota tion of the adding'wheels whenever sub traction is to be performed.

General, descm'ptiom-The present inven= tion is based upon and operated In a very similar manner to the machine described in my pending patent application No; 470,108,

filed December 3, 1908 and which is also ,fully shown and described in British Patent N 0. scription in the above .mentioned patent is voluminous and enters into much detail, it

will be unnecessary in this application to go details of the m chine which have no direct to arrange,

28,258 of 1908. Inasmuch as the debearing upon the accumulator or the mechanism for controlling the same.

The machine shown includes in the drawings only the calculating mechanism. The case for surrounding the machine, the carriage for holding the paper on which the printing is done; the inking mechanisms are not shown at all, they being in all respects the same as inthe above application and patent referred to and could be altered to suit individual requirements if this mechanism was applied to any other machine than the one shown and described in the application and patent above referred to. The printing mechanism is only in one view in Figure 2.

In Fig. 2, is shown a vertical center section of the machines, and illustrates my preferred method of arranging the machine as a duplex, 2'. 6., a two accumulator machine,

though of course, it is evident that any other arrangement of the two accumulators could be made equally well to meetthe convenience and space at the command of the'designer and it is also evident that by spreading the two accumulators, with a little more space between them, it would be entirely possible two, four or any other number of accumulators back of the two shown by extending the actuating rack straight back for the purpose of engaging such of these accumulators as might be desired. In this description but one of the accumulators and its connections will-be described, and inasmuch as each accumulator has a complete set of operating keys and connections, in all respects the same as the set shown, it is evident that the second accumulator would work in all respects the same as the first.

All views shown are in the nature of diagrams with all unessential parts omitted for the sake of clearness.

Referring to the drawings :Fig. 1, a right side elevation showing theoperating ,handle and the parts outside of'the vertical side frame to which the cross members of the'machine are attached. Fig. 2, a vertical center section showingparts of the machine in their normal position, and the relative position of the two accumulators. Fig. 3, a. left side elevation with the handle in the normal position and the adding key, sub-total key and subtraction key in their elevated PQSit-ion. Fig. 4, a left side elevation with the mechanism in position assumed when the handle is at the; end of its forward stroke, the subtraction key having been depressed. Fig. 5, a left side elevation showing the'subtraction key depressed with the handle in its normal position. Fig. 6, a left side elevation --key release bar is moved. Fig. 10, a vertical section through the accumulator, handle in normal position and accumulator set for addition Fig. 11, detail of the carrying detent sector. Fig. 12, vertical section through the accumulator, parts in normal position with the handle at rest, mechanism set for subtractiom Fig. 13, elevationof carrying bar operating mechanism. Position normal, accumulator set for addition. Fig. 14:, section showing'the wheel frame cam. Position with handle normal. Fig. 15, a vertical section of the accumulator setfor addition, position of parts with the carrying bar at its extreme forward position, which position is reached just prior to the handle reaching its extreme forward position when adding. Fig. 16, vertical section through the accumulator set for subtraction, parts in the same relative position as parts shown in Fig. 15.

Fig. 17, elevation of carrying bar operating mechanism set for addition, position of parts same as the position shown in Figs. 15 and 16. Fig. 18, detail showing the wheel frame cam, position same as position of parts shown in Figs. 15, 16 and 17. Fig. 19, vertical section through the accumulator, parts set for addition, position of the parts that assumed when the handle is at the extreme end of its forward stroke in adding. Fig." 20, verticalsection through the accumulator,

parts set for subtraction,.position of parts is that assumed when the handle is at the extreme end ofits forward stroke. Fig. 21, elevation" of the carrying bar operating mechanism, parts set for addition and position the same as in Figs. 19 and 20. Fig. 22,

detail showing the wheel frame. cam, posit1on thesame-as for parts inFigs. 19, 20, and 21. Fig. 23, a vertical section through the accumulator, parts set for addition, po-

sition of parts that assumed when the handle is on its return stroke and the racks have completed their forward movement, but the adding wheels have not been disengaged from the racks, the carrying hook is tripped so that carrying will be performed when the wheels are brought into mesh with the carrying detent sector. Fig. 24, a vertical section through the accumulator, parts set for subtraction, position of parts that assumed when the handle is near the end of its forward stroke, the adding wheel has tripped 'the subtracting hook for the purpose ofsection through the accumulator, parts set for addition, position that assumed when the handle has returned to its normal position, the carrying bar released and carrying accomplished. Fig. 28, a vertical section through the accumulator, parts set for subtraction, position that assumed when the handle has reached its normal position, carrying bar released and carrying accomplished. Fig. 29, elevation of the carrying bar operating mechanism, set for addition, position of parts that assumed when the handle is returned toits normal position.'

Fig. 30, detail showing wheel frame cam, position. assumed when the handle has reached its normal position. Fig. 31, top view or plan of the accumulator, broken through the center in order to shorten the view and showing the relative position of the operating parts and of the parts controlling the movement of the carrying bar. Fig. 32, detail showing the plate 53 and the side member N, of the wheel frame; Fig. 33, detail showing the plate N and the carrying segment N mounted thereon. 'Fig. 34, detail of the adding hook N. Fig. 35, detail'of the adding cam, N Fig. 36, detail of the subtracting hook N Fig. 37, detail of the subtracting cam, N

In general, the operation of this machine is dependent upon a forward and backward movement of a sliding rack-see. Fig. 2. This rack, R is mounted "to slide on-twc slotted cross bars K and R. The movement of this rack R backward and forward is limited for thepurpose of addition and subtraction by the stops K secured to the verticalsliding key stems of the keys, K K K etc, to K. The key, K does not limit the travel of the rack, but permits it to go its full stroke which is limited by the downward projections at the ends of that part of R which slides in the groove in the bar Kt These stops, K areso arranged that they engage steps on the upper edge of the rack R and these steps and the stops,

more a distance of two teeth and th st 23 130 I .rack to move a distance of three teeth; etc.,

up to K, which serves the purpose of unlocking the rack R, by releasing the rack lock 68, and permitting the rack, R to move its full travel or nine teeth.

The rack R is moved in a rearward direction by means of the springs, R which are connected at their rear ends to a bar, R extending between the side'members of a bail, 45 which bail is secured to the shaft R and rotates with it. Mounted on-the shaft R are a series of bell cranks, it, having three projecting arms, one projecting forward for the purpose of operating the 0 printing triggers, P, the other arm extending rearwardly for the purpose of connect ing to the link P which serves to rotate the type sector 1 and if the bell crank, R is rotated about the shaft R the connecting link P will cause the type sector P to rotate about its center and bring the desired type to the printing line. The third arm from the bell crank, It extends in a downward direction and carries a pin R which engages a vertical slot inthe lower side of the rack, B so that when the rack R moves forward and backward it communicates this motion to the bell crank B through the pin R and when the bail 45*" "lower extending arm of the bell 'crank,TR

is'for the purpose of obtaining forced aline ment of the type on the sector P and this alinement segment R is secured firmly to the lower arm of the bell crank R The alinement of the type through the segment R is brought aboutthrough the insertion of the bladeR mounted on the forward side of the alining frame R which in turn is mounted upon the shaft R 1 The rotation of the shaft R and the rotation of the shaft R in their proper relative time is brought about by means of a roller 0 Fig. 1, mounted on the end of arm, 0, which is secured to and rotates with the shaft This shaft, is rotated by means of the handle 0 which may be moved from position shown in Fig. 1, through an angle of 60. degrees in a direction toward the left. The handle ()is not secured positively to theshaft O but to a plate 0 of irregular shape. The plate 0 carries a small tumbler O which ratchets past the teeth of a full stroke segment, 0, and reversing at the end of the stroke, comes back to the position as shown in Fig. 1. A lower extending arm of this plate, 0 is connected to a large spring 0?, the other end of which is connected to a pivoted arm, 0

the upper end of'which is connected to the link 0 which in turn is connected to the upward extending part of the arm 0.

The object of this linkage is to provide a means whereby the speed of the shaft 0 may be controlled by a suitable governor irrespective of the speed at which the handle 0 maybe operated as is customary in all adding and listing machines of this class.

When the handle 0 is moved downward it extends the spring 0 which in turn through the lever 0 moves link 0 ma forward direction, see Fig. 1, and so 'has a tendency to move. the arm 0 in an upward direction and so cause the roller 0 to move upward in the slot of the cam O which in turn is secured to the shaft R It will be seen from the nature of the cam 0 that this travel of the roller, U will cause the rotation ofthe shaft R through a limited arc in the reverse direction from the hands of a clock. This movement of the shaft R causes the bail 45 Fig. 2, to' swing through the proper distance and so cause the springs R to extendand move the racks, R

in a rearward direction to apossible distance 7 equal to nine teeth. The movement of the shaft R however, does not take place during the entireperiod of rotation ofthe shaft 0 but only during the middle period of its travel. It will be noticed that the cam 0 Fig. 1, has a portion of its length at the beginning and end of thetravel of the roller 0, concentric with the shaft 0 These concentric periods will consequently permit the shaft to rotate while the shaft R is remaining stationary, and thus permit other operations of the machine to take place before and after the racks B have moved.

0 The roller 0 has a counter part extendv ing to the rear ofthe arm 0 and this rearthe segment R thus bringing the position This rotationof the shaft R of the bell-crank, R to a permanent location irrespective of the exact position of the stops K or the other means of limiting the travel of the rack R. It will thus be seen that during the forward and return stroke .of the handle 0 the racks R are moved from theirposition of rest as shown in Fig.

2, to the rear on the forward stroke of the handle 0, and are returned to their normal of toothed wheels as shown inthe drawing,

0 in either a forward or backward direction, but only through the middle portion of the stroke of'the handle.() in both a forward and backward direction. I

In speaking of the handle stroke, it will be assumed for the purpose of eXplanation that the handle, 0 will be moved at a speed permitted by the governor controlling the speed of the shaft 0 so that for all purposes of explanation, the return of the handle 0 and the shaft 0 will be considered as the same in time. It is also evident that theprinting type P are positively connected through the links P and bellcranks R to the racks R and that any motion of the racks R will communicate a corresponding motion to the printing type P.

The adding and. subtracting accumulat01=.This accumulator consists of a series each Wheel having twenty teeth. The wheels are mounted upon a common aX1s and are caused to engage and to disengage by being lifted into and out of engagement with the teeth of a sliding rack or actuator, the rack being moved a distance in number of teeth .to correspond to the number of units to be added in that particular denomination. A

two pointed cam with the points diametrically opposed, is secured to each tooth wheel, the function of this cam being to trip the mechanism for causing carrying and also to serve as a stop when the wheel is moved in a reverse direction from'adding for the purpose of-obtaining a total. A detent is provided for holding the toothed wheel from rotation when it is out of mesh with the rack, and this detent is made in the form of asmall pivoted segment and so arranged that directly as the wheels are disengaged from the teeth of the rack they come into engagement with the teeth of the detent segment. Whenever a toothed wheel is rotated through a period of ten teeth and y it becomes necessary to rotate the adjoining wheels one tooth in one direction in the case of addition and in the reverse direction in the case of subtraction, the holding detent segment is caused to rotate about'its pivot a distance of one tooth. Suitable mecha-' nism is provided for causing the-detent segment to make this movement after the adding 'Wheels have come into mesh with it. These same meansscrve the purpose or holding the detent segment stationary when carrying isnot to be performed.

In mymachine I prefer to assemble the accumulator as a separate unit or section of the machine and then attachthis section to the balance of the machine by screws or other suitable means, having as few connection members for operating the accumu- 1,2oa,ees

mul-ator in detail I will call attention to the arrangement of the drawings beginning with Fig. 10, and Fig. 30.

The upper figure on each sheet represents a vertical cross section through the accumulator'with the parts set for addition. The second figure of each sheet, that is, 12, 16, 20, etc., represent the same section through the accumulator with all of the parts in the same relative position in'regard to the position of the operating handle, O ,-but with the accumulator set for subtraction. The third figure of each sheet, 71. e.-, 13, 17, etc., represent a vertical section through the machine showing the operating levers on'the outside of the frame N, which serves to move the various parts of the accumulator which are not actuated by the racks, R and the arrangement of the parts shown in Figs.

l3, 17, 21, etc., correspond'on each sheet with the position of theparts' shown for the figures immediately above them. The

' bottom figure of each sheet, Figs. 14, 18, 22,

etc., show a detail of the cam N, which wrves to raise and lower the adding wheel, N out of and into mesh with the racks,

B. This system of arranging the figuresnecessitated the duplication of certain figures on the sheets, particularly such cases as Figs. 13 and 29, 14 and 30, 21'and 25, 22

extending to and, including and 26; but the system as a means of illustrating may make the description a little 'clearly'shown. There aretwo verticalcast iron frames, N which serve as -..a foundation upon which the structure is erected. These frames, N join on and are secured to the main' side frames of the machine itself as indicated in outline in Figs .'3 and 4. Be-

tween these two side frames, N, there extends certain horizontal shafts, N, see Figs. 32 and 33. These shafts have collars sur rounding them and the shafts pass through plates,

means for holding the plates N and 53ii n 'a vertical position and the proper horizontal distance apart. There are two plates,

53 which are placed one at the right-hand side .and the other at the left-hand side of the group of plates N The adding wheels N are mounted on a Q horizontal shaft. N which extends through a series of plates N and 52, the end members N of the series being pivoted to the plates 53 at N, see Fig. 32. A plate 51), see Fig. 31,,is mortisedinto the ends of the pieces N and 52"a nd serves as a brace for 53 and N the collars serving as enters the slot in a cam N N which also extends through the various plates N and 52 The only difference between the pieces N and 52 is that the end members N are made somewhat heavier and the pieces 52 are shortened so'that they do not extend down so far as to take in the hole for connecting the stud pivots N. The shaft N is threaded at each end where it'passes through the plates N and when the adding wheels N are mounted, suitable nuts are screwed on the ends of the shaft Niand on being tightened form the combination of parts into a framewhich is reasonably rigid and this frame as a whole swings about the pivots N in the plates 53 see Fig. 32.

The shaft N extends through the side plates N at each end and terminates in a small roller Ni", see Fig. 14, which roller mounted upon the shaft N The slot in the cam N is of such design that the partial rotation of N with shaft N will cause the roller, N and 5 the consequently the shaft N to advance to or recede from the. shaft N and the position of the shaft N is such that as this cam N is operated it moves the shaft N so as to cause the adding wheels N to engage and disengage the teeth of the rack R Mounted in the wheel frame consisting of parts just described and upon a shaft N which extends through the various plates N and 52 are a series of hooks, N and N whose points come into the plane of the. two pointed cam N secured to each of the wheels N The shape of these two hooks N and N is clearly shown in Figs. 34 and 36. They are in each case provided-with a spring N so arranged that its tension causes the two points of the hooks to tend to move toward the center of the cam N The shape of the point of the hook, N is such that in rotating the cam N in a direction so that it strikes the point of the hook N while moving in a direction toward the shaft N the hook N will rise up and the point of the cam N will pass underneath it. On the other hand if the rotation of the cam N is in thereverse direction so that it engages the hook N in a direction moving from the shaft, N the cam N will stop against the inside of the hook N I y The defeat segment-The small three toothed segment N is pivoted at N see Fig. 11, to each of the plates N. This segment N has extending outward from one side of it a pin, N and the position of the teeth of the segment N 'issuch that as the wheel N is disengaged from the teeth of the rack B it at once engages the teeth of the segment N and when in full engage- Wheel N just clear the teeth of the rack To maintain the position of the segment N there is 'rovided twoirregular shaped cams N an N, the exact form of which is clearly shown in Figs. 35 and 37. These cams N 55 and N are pivoted to the plates N 53 at N. each cam is provided with an eccentric and somewhat irregular shaped slot which embraces pin N The slot in the cam N is so arranged that its rotation about'its center N will cause the pin N to move the segment N toward the right in Figs. 10 to 30, while the slot in the cam N is so designed that a rotation of the cam N about its center N would cause the pin N to rotate the toothsegment N in a reverse direction, to the left, in the aforesaid figures. lVhen both of the cams N and-h are in their uppermost position the shape of the slots at their lower ends is such as to hold and the upper extending arm of on the hook 1 engages the cam ,1 on the part marked X, see Figs. 3437, while the turned over end marked Y on hook N engages the part marked Z on the cam N.

A suitable spring N is provided for each of these cams N and l 56 and tends to rotate them so that their upper end shall move in a downward direction and conse quently to move it against the latched-up position which is maintained by the hooks N and N The carrying bmaThe horizontal bar N having upward extending arms at each end, is pivoted at N, see Figs. 13 and 31. to the side frames N The bar N is normally held in its retracted position by a spring N and is stopped by the collar on the shaft N. The pin, N see Figs. 13 and 31, serves as a means for swinging the bar N about its pivots, N The function of the bar N is to restore the cams N and N to their latched position by means of the hooks N and N after the cams N and B! have been unlatched in the process of carrying.

The shift bar.Extending between the side frames N and through the one on the left-hand side, there is an irregular shaped bar, N the function of whichis to block the action of oneof the hooks N and N9 and at the same time, toblock the action of one of the camsiN and N, as will be clearly seen by an examination of Figs. 10

and 12, and also of the Figs. 34.37. In Fig. 10, the upper projecting ridge on the bar N engages the part marked (Z, Fig. 37 on the cam N and so would prevent the cam.

N from rotating about its center N and so moving the pin N on the segment N; at the same time the lower projecting edge of the bar N has engaged the projection (b) on the hook N and has so moved the hook N as to take its point clear of the path of travel of the points of the cam N so that in this position of the bar N the hook N and the cam N are totally inoperative as-shownin Fig. 10. In Fig. 12 the bar N has been rotated through a limited angle and this upper projecting edge has come in contact with the projection C (Fig. on the cam N and the lower edge of N with A, on the hook, N and has moved the hook N so that its point has passed out from the path of travel of the cam N and the hook N and the cam N are rendered inoperative. I

With the above description of the separate partsand their mode of operation we will now consider the means for causing the machine to add.

The operation of addit0n.Referring to Fig. 10, the parts will be found in their relativeposition at the time that the handle 0 is in its normal position as shown in Fig. 1, in which position certain of the numeral keys K are depressed. The handle 0 is now "drawn forward, which is to theleft in Fig. 1, and the rack R moves to the right as in Fig. 15. After the rackR has moved, the shaft N is rotated and the wheel N is caused to engage with the teeth 'of the rack It, the engagement of the wheel N with the teeth of the rack R being caused by the movement of the cam N to the positionshown in Fig. 18. At this position of the cam N the handle, 0 has not quite concluded its forward stroke and the'full stroke ratchet O has not completed its travel in the tooth segment, 0, see Fig. 1, to the last notch in which it reverses itself for the return stroke of the handle 0. At this position of the cam, N the carrying bar N has been swung to its extreme forward. position by means of the mechanism clearly shown in Figs. 13, 17,

21 and 25. This mechanism operates as follows: On the end of the shaft N there is a crank, N which serves for rotating it. The

lower end of this crank N" has on it a roller N which roller, N engages an irregular shaped cam piece N. This cam has an upward extending horn on the right-hand side, I

Figs. 13 and 17 and when N is moved from position shown in Fig. 13', to the position shown in Fig. '17 this upward extending horn engages the roller on the end of the piece N, which is pivotaly connected to the carrying bar N and moves -the bar N to parts X and Z engage the turned over ends Y and W-of the hooks N and N The further forward motion of the handle 0 to its extreme limit in a forward direction moves the cam N"' .to the position shown in Fig. 2 2, but this motion from the position shown in Fig. 18, to the position shown in Fig. 22 of the cam N does not changethe position of the shaft N in relation to the shaft N because this portion of the slot in the cam N is concentric with the shaft N In this position of the parts shown in Fig. 21, the piece N has this roller pass over the upper end of the irregular cam N and the pin N extending from the side of the carrying bar N is" dropped back until it engages the hook N and the caryingv bar N is retracted from its contact from the cams N and N leaving a slight gap, G, see Figs. 19 and 20, between the carrying bar and the aforesaid cams. The handle 0 now returns to its normal position and in so doing rotates the wheel N while the racks R are returned to their normal position. In Fig. 19, the rack R .is within one tooth of its restored position and the cam-N is in a position just before engaging the hook, N. Just before the handle, 0 reaches its normal position as shown in Fig. 1, the parts will assume position shown in Figs. 23, 25 and 26. In this position it will be observed that the cam N has passed the point of the hook, N and raised the same causing the -lower end of the hook at W to disengage the cam N to raise wheels N out of en gagement with the teeth of the rack R and engagethe teethof the segment N after which there is a slight movement of the roller N on the end of the crank N, which engages the upward extending arm' of the hook, N and causes the hook N to disen gage the pin N on the carrying bar N and the carrying bar N through the influence of the spring N is moved totheposition shown in Fig. 27, and the cam N is moved to follow it through the influence of the spring N thereby moving to its lowered position and causing its cam slot to move the pin N in such a. direction as'to cause the adjacent wheel N to rotate a distance of one tooth in the Zsamev direction which the wheel has been rotatedby the return of the racks R. On the next forward stroke of the handle 0 the Wheels N cam N i will take R as before and near theendof the forwardstroke of the handle, the carrying bar N will move forward and relatch' the on the hook N m This relatching place while'the wheel N is in engagement with the teeth of the rack R The operation of subtracti0n.The relative position ofthe' parts in the act of subtraction are clearly shown in sequence of figures beginning with Figs. 12, 16, 20, 24

I N to disengage from the part. Z of the cam and ending with Fig. 28. In Fig. 12, it will be seen that the bar N has been turned from the position shown in Fig. 10 and that the upper projection on this bar is now in contact with the cam N at c, Fig. 35 and the lower projection of the bar N is in contact with the upward projection a on the hook, N and that N and N are consequently rendered inoperative.

When subtraction is to take place in this machine, the wheel N is caused to engage with the teeth of the rack, it before the rack R has been moved. The travel of the rack R being limited by the depression of the keys K 21i on the key board .or otherwise. The wheelN will be rotated in the reverse direction from that of adding and it will reverse itself as many teeth as the rackR moves toward the rear of the machine and consequently as'many teeth as the figure on the key stem which limits the travel of the rack R. In Fig. 12 the parts are shown with the handle 0 in its normal position of rest. In Fig. 20, the handle has advanced, the wheels N have been de-' pressed into the teeth of rack It and the rack R has advanced until the cam N has come into position to engage with the pointof the hook N. In Fig. 24, the handle O has reached its extreme forward position and the rack It has advanced the cam N still farther and it has passed the point of the hook N depressing the same and causing the other end, Y, of the hook zN permitting the cam N to swing downward under the influence of the spring N until it comes in contact with the carrying bar N This distance, however, is not sufficient to cause the cam N to movethe pin N and the segment N. In Fig. 28 thehandle, 0 has returned to its normal position, the carrying bar N has been released bythe hook N and has retracted to its rear position and the cam N has defollowing the movement of scended to its lower position, this lower end the carrying bar N The slot in its upper end which engages the pin N moves the segment N in a forward direction one tooth and causes the adjacent adding wheel N, to the left,

to be moved through a distance of one tooth in the direction which the wheels N move, when subtraction takes place. On the next bar N is moved forward at the endof the forward stroke of the handle, 0 and relatches the cam N and the hook N.

Taking .a t0taZ.-In the taking of a total the mechanism is in the same relative position .as shown in Figs. 10,15, 19, and 27, butthe action 'of' the adding wheels N takes place in the same period of time that-is employe in subtraction, that is, the wheels N? are caused to engage the racks R prior to the movement of the racks R to the rear and this movement of the racks R reverse the direction-of rotation of the adding wheels. N F the same as in subtraction until the cam N abuts against the inside of the hook N at which place it will stop and arrest further action of the rack R. It will consequently permit the rack R to move as many teeth as there are units accumulated from this starting position of the wheels, N

If the wheels are to be cleared and made ready for a new addition the wheels are lifted out of engagement with racks R before the racks begin their return stroke.

If, onthe other hand, it is desired to retain the .total in the machine and'add to it, the racks R are returned to the starting point before the wheels N are raised out of engagement with it.

The adding key and thecdrriage oonneci to engage and disengage from the rack R5),

is connected by the link D to the upper end of the flying lever D ,.which flying lever is pivotally mounted upon the'plate D secured to the shaftO}. Mounted on the pivot which secures the link D to-the flying lever D is an abutting cam D which is held in, its proper place by -a small spring, and is capable of rotation about this same pivot. In its normal position the piece D will contact with the stud D as shown in Fig. 4, when the plate D has completed about three-quarters of ment, and whenD contacts with D, the combination of the plate D, the flying lever D and the abutting cam D form a Solid crank from the shaft 0 to the link D and the further movement of the shaft 0 rotat dition. There is, however, another train of 7 its forward move-' from the position mechanism which normally prevents the abutting cam D from: engaging the stud D This mechanism consists of the piece D pivoted about its middle to the side frame, the

I actuated by a suitable spring, engages a about sixty degrees.

. 4, in which position it is maintained by the upper end of the piece D carrying the projecting pin D. This pin D is held in its upward position as shown in Fig. 3, by a link I) which is pivoted at its lower end to the piece D, which in turn is pivoted to the side frame. The other end of the piece D is in the path of travel of the plate D and when D is in the position shown in Fig. 3, the link I) raises the pin D and moves the lower end of the piece D so that it is latched in this raised position by the piece D When the pin D is in this elevated position as shown in Fig. 3, the upper end of the abutting cam D would engage the pin D when the plate I) is rotated with the shaft 0 and this would cause the lower end of the abutting cam D to miss the square stud D and the conse uence would be that the rotation of the sha t O and the plate D would in no way affect or move the crank N. To permit the pin D on the piece D to begindescent and be out of the way of the upper end of the abutting cam D it is'only necessary to elevate the forward end of the trigger piece D and this is'done by two separate means, One is a link D which is positively raised by a suitable projection on the carriage of the machine, the mechanism not being shown. The other means being the latch L for the adding key K. This latch L is pivoted in the side frame of the machine, its lower end terminating in asuitable pin for engaging the end of the trigger D and its upper end notch in theback side of the key stem of K and when the latch L engages this notch, it raises the forward end of the trig ger, I) which permits the pin D to de-' scend when the plate D moves and permits the piece D to follow it.

No mechanism is shown for operating the trigger D and its connecting link D from the carriage, as this can .be arranged in any suitable way depending upon the circumstances and design of the particular machine in which this mechanism is employed. The operation of this mechanism is as follows: The handle 0'' is operated which causes the shaft O to rotate in a clock-wise direction on Fig. 3, through an angle of When the plate D has moved through an angle of about fortyfive degrees, the abutting cam D engages the stud D? on the plate D which forms a rigid connection to the link 1), and the further. movement of the shaft 0 rotates the crank N to the position shown in Fig.

spring detent N On the return stroke of the handle O the plate D moves to the travel of plate D causes the flying lever.

D to push the connecting link D and so swing the crank N from the position shown in Fig. 4 to the position shown in Fig. 3, and this motion of the 'crank N takes place after the racks B have been restored to their normal position.

The total and sub-total keys.-The taking of a total or sub-total on this machine is accomplished by the depression of one of two keys, which two keys are altogether similar in their action, with the exception that the total key is not released to become inoperative. until near the end of the return stroke of the handle 0 while in case of a sub-total the key is released near the end of the for- Ward stroke of the handle 0 The operation of this mechanism can be clearly seen in Figs. 3 and 4. The key K" is a sub-total key. ()n being depressed it will become latched down by the engagement of the piece 55 with the notch in the back side of the key stem of K. This latch 55 is pivoted about whenever the latch 55 engages the key stem of K. This movement of the piece L fro-m the position shown in Fig. 3 to the position shown in Fig. 4 depresses the piece 58 1 by means of the cam on its upper edge, the piece 58 being pivoted about the same center with the piece 60 and connected thereto by'a suitable spring. When the piece 6O is raised-to the position as shown in Fig. 4, the left hand end of the piece 60 will come into the path of the small roller on the lower end of the flying lever D and form an obstacle to the movement of the said roller on the end of the flying lever D Pivoted on the piece 60 is a piece L which is held in the position shown by a suitable spring. v I

hen a total is to be taken the total key,- which corresponds to the key K, is depressed and the piece 60 and the piece L y at once assume the position shown in Fig. 4.

The rotation of the shaft 0 with the plate D causes the flying lever toengage the piece 60 with its lower end and roller, and the first fifteen degrees of the motion of the plate 1) causes the flying lever D and link 

